Cosmic Distances

Understanding the vast scales of the universe.

Distance Sets
Real-world distances with light-travel time and commercial flight equivalents.
Earth-Moon
384,400 km
Mean distance
Light time
1.3 s
Plane time
17.8 days
Assumes 900 km/h
Earth-Sun
1 AU (149,597,870.7 km)
Mean distance
Light time
8.3 min
Plane time
18.96 years
Assumes 900 km/h
Earth-Mars
225,000,000 km
Average distance
Light time
12.5 min
Plane time
28.52 years
Assumes 900 km/h
Earth-Jupiter
588,000,000 km
Average distance
Light time
32.7 min
Plane time
74.53 years
Assumes 900 km/h
Sun-Neptune
4.495 billion km
Average distance
Light time
4.2 h
Plane time
569.75 years
Assumes 900 km/h
Sun-Proxima Centauri
4.2465 light years
Closest star system
Light time
4.25 years
Plane time
5,092,258.29 years
Assumes 900 km/h
Sun-Andromeda Galaxy
2.537 million light years
Mean distance
Light time
2,536,991.83 years
Plane time
3,042,284,064,694.4 years
Assumes 900 km/h
Distance Timeline (log scale)
Earth-Moon384,400 km
Earth-Sun1 AU (149,597,870.7 km)
Earth-Mars225,000,000 km
Earth-Jupiter588,000,000 km
Sun-Neptune4.495 billion km
Sun-Proxima Centauri4.2465 light years
Sun-Andromeda Galaxy2.537 million light years
Scale is logarithmic to compare local and intergalactic distances on one line.
Cosmic Converter
Convert between astronomical distance units.
1.4960e+8

1 AU ≈ 150 Million km (Earth-Sun distance)

1 Light Year ≈ 63,241 AU (Distance light travels in one year)

1 Parsec ≈ 3.26 Light Years (Used in astrometry)

Cosmic Distance Scale
How long does light take to reach these destinations?
1
Moon
384,400 km
Solar System
1.3 seconds
light travel
2
Sun
1 AU (150M km)
Solar System
8.3 minutes
light travel
3
Mars (closest)
0.5 AU
Solar System
4.2 minutes
light travel
4
Jupiter
5.2 AU
Solar System
43 minutes
light travel
5
Neptune
30 AU
Solar System
4.2 hours
light travel
6
Voyager 1
~160 AU
Solar System
22 hours
light travel
7
Proxima Centauri
4.24 light years
Nearby Stars
4.24 years
light travel
8
Sirius
8.6 light years
Nearby Stars
8.6 years
light travel
9
Vega
25 light years
Nearby Stars
25 years
light travel
10
Center of Milky Way
~27,000 light years
Beyond
27,000 years
light travel
11
Andromeda Galaxy
2.5M light years
Beyond
2.5 million years
light travel

Fun Fact: When you look at the Sun, you're seeing it as it was 8 minutes ago!

Light from Andromeda Galaxy started its journey before humans even existed.

What is a Light Year?

A light year is the distance that light travels in one year in a vacuum. Since light moves at approximately 299,792 km/s, one light year equals about 9.46 trillion kilometers.

It's important to note that a light year is a unit of distance, not time!

What is a Parsec?

A parsec (parallax second) is a unit used in astronomy, equal to about 3.26 light years or 31 trillion kilometers.

It's derived from the method of measuring stellar distances using parallax. The nearest star, Proxima Centauri, is about 1.3 parsecs away.